You are better off getting a Master's in the field of your choice from a top-ranked university. It is not so much what they teach you, it is the following:

1. You get exposed to a wide range of fields so you can pick and choose what really fascinates you.2. You meet a lot of great people and network, so you can open more doors that just mailing resumes.3. Finally, going back to school gives you the time and bandwidth to think through these issues (rather than the daily rigmarole of a job)